Mastic Sealing in City of Westminster
Sealant work in City of Westminster for main contractors, managing agents and facilities managers: mastic sealing for building owners, managing agents and housing associations, with a fixed quote first.
- No planned programme for sealant
- Brittle perimeter mastic across a building
- Water getting in round frames after rain
Mastic sealing near City of Westminster
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
Mastic sealing in City of Westminster, done properly
On a residential block, the work happens around people’s lives. Dates, areas and the order of work are agreed with you in advance so you can let residents know what is happening. Entrances and stairwells are kept in use throughout. If you are dealing with a mix of products and colours from past repairs and open joints in brickwork or panels, we can put it right. Sealant contractors, mastic applicators, sealant specialists: whatever the job title on the order, in City of Westminster it comes down to the same thing: the right product in a properly prepared joint.
Planning mastic work on a London block means notices to residents, access to flats and agreed working areas. We work to the agent’s notice and access plan, so residents know what’s happening.
Whoever the client is, the cover is the same: twelve months on the work we carried out. It doesn’t extend to damage, faults in the building or work by others, and we’re upfront about that.
- Where
- City of Westminster (W2, NW8, W9, SW1V)
- Region
- Greater London
- Guarantee
- 12 months on every job
- Quote
- Quoted before any work starts
- Phone
- 01277 525 020
- Page updated
- 3 November 2026
Commercial clients in City of Westminster
Hospitality, education, healthcare, office and retail clients come to us directly as well. The work is planned around how the building runs, so guests, pupils, patients or staff are disturbed as little as possible.
When you manage a building on behalf of an owner, clear figures and clear communication matter. You get a fixed quote, an agreed scope and a walk round at the end.
Surface by surface
External movement joints
Brickwork, blockwork and panel joints let a building move. Failed sealant in a movement joint lets water in.
Estate-wide resealing programmes
Using the same products throughout keeps the estate consistent and easier to manage.
Planned mastic for City of Westminster portfolios
In London, mastic work on a block goes through the managing agent or landlord, with notice to residents. We plan around the notices and access you arrange.
If you are responsible for a building such as St Mark's, frame and door mastic needs the same attention as any other property. Student blocks close to universities like University of Westminster, 0.7 miles to the north-east of City of Westminster, are easiest to work on between tenancies.
City of Westminster is about 3 miles west of London, in Greater London. Commercial clients in City of Westminster can call on us for mastic joints. City of Westminster is one of 764 places we cover in Greater London.
Postcode districts covered here: W2, NW8, W9 and SW1V. We cover commercial and managed buildings on Portman Square, Grosvenor Square and Cavendish Square. Main routes into City of Westminster include the A4 and A5, which helps when planning parking and deliveries for the job. Close to City of Westminster, our area also takes in Marylebone (1 mile north-east), Mayfair (1 mile south-east), Tyburn (1 mile west), Burlington Estate (1 mile south-east) and Connaught Village (1 mile west). A short drive away, we cover London (3 miles south-east), Shoreditch (3 miles east), Walthamstow (7 miles north-east), Hoxton (3 miles north-east), Whitechapel (4 miles east) and Hampstead (3 miles north-west). City of Westminster is one of the busier places in Greater London, and its commercial and public buildings are all within our area.
Around City of Westminster
Around City of Westminster, our work takes us to commercial buildings near LITE Regal International School, Royal Society of Medicine Library and Devonshire Arms. Other local landmarks include The St Marylebone CofE School (0.5 miles north) and Hyde Park (0.6 miles south-west). City of Westminster has its own railway station: Bond Street station. Well-known places in the area include Dunhill Museum & Archive (less than half a mile north) and Kingly Court (0.6 miles east). Not far away are Serpentine and Primrose Hill.
Maintenance after handover
For the best life from the joints:
- Include mastic in your cyclical inspections
- Make it easy for occupiers to report draughts
- List the paperwork your organisation requires when you send details
- Have the asbestos survey to hand for older buildings
If paintable sealant was used, decoration can follow once it has cured. Silicone usually can’t be painted, so keep decorators off it unless told otherwise.
Budgets are easier to plan when sealant is part of planned maintenance. A programme can start with the worst buildings and work down the list.
Also near City of Westminster
What else we do in City of Westminster
Questions we are asked in City of Westminster
Do you cover business parks and estates near City of Westminster, such as Brompton Cross District Shopping Centre.?
Yes. Our area takes in City of Westminster and its surroundings, with estates and business parks such as Brompton Cross District Shopping Centre. Included. To start, just call the office on 01277 525 020 or email a schedule or drawings with the unit, the joints involved and your access times.
Can you quote for a block close to Bond Street station?
Yes. Managing agents, landlords, property factors and housing associations are who this service is for. Send the address, photos of the elevations and your access arrangements, and we’ll give a fixed quote.
How long will the new sealant last?
There isn’t a single answer, since movement, weather, cleaning and use all affect it. Regular checks let you plan resealing before leaks or damage.
How many days will you need on site?
We plan the time on site around your programme and access. We will give you an estimate of time on site when we quote.
Do you check for asbestos in old sealant?
Asbestos removal isn’t part of our work. Anything suspect is tested before we carry on in line with the dutyholder’s asbestos management.
What guarantee do you give on resealing?
Every building we reseal has a 12-month guarantee. It applies to our workmanship rather than damage or problems with the frames.
Do you seal on top of existing sealant?
No, never. Overlaying old sealant is a frequent cause of early failure, so everything comes out first.
When to call us in City of Westminster
The edges of the material itself sometimes break away for example where render or brick edges crumble. If the edges are unsound, we say so before quoting the sealing.
Site and facilities staff are often the first to spot these:
- Brittle perimeter mastic across a building
- Complaints coming in block by block
- Damp patches beside frames
- Failed external movement joints
If you look after a block within reach of Bond Street station, under half a mile to the east of City of Westminster, frame and balcony mastic can be renewed on one programme.
What to look for in a quote
- What the guarantee covers, and for how long
- What level of public liability insurance do they hold?
- Are they CHAS accredited or on Constructionline?
- Their approach to joint depth and backing
On site: what to expect
A typical day starts with protection: masking tape along the joint edges and sheeting over anything nearby. The work itself usually takes a day or two for a single block, longer for an estate programme, and we clear our waste as we work. In City of Westminster, most buildings stay in use during the work, so zones and timings are agreed with whoever manages the building. Areas are handed back as each section is finished.
- Each block or building is walked and the failed joints recorded with the likely cause.
- We send a fixed quote that sets out the joints, the products and the programme.
- The programme is fixed with you, including dates you can pass on to residents or tenants.
- We remove the old mastic completely and clean the joint faces back.
- Backing rod and primer go in as the joint requires, then the new bead is placed and tooled.
- Each building is checked on completion and the work carries our 12-month guarantee.
Before we start on site
- Make sure the joints can be reached
- Tell staff and tenants when we’ll be in
- Tell us which areas need to stay in use
Get a fixed quote
Send details, get a quote, we seal, guaranteed: that’s how every job runs. The first step is to call 01277 525 020 or use the quote form with what you know.
Related advice
Leave it or put it right?
Failed perimeter mastic lets cold air in around frames, and they often blame the windows. In many cases, new perimeter sealant deals with it where the frames themselves are sound. In a London building, a failed joint rarely affects only one party: water travels through shared structures, and a small leak becomes a dispute between occupiers. Putting it right early is less disruptive than dealing with the consequences.
Pricing mastic joints depends on how many there are, their condition and the access. Ask us for a fixed quote.
Why us?
- Fixed quotes based on photos, drawings or a visit
- Colour options checked against the specified product
- Failed material removed, not covered up
- Public liability insurance in place